PISTON 2344814 - Caterpillar

ENGINES
3600 FAMILY OF ENGINESProblem:
Occasionally there may be insufficient wrench clearance to tighten the 679921 Tee (3) correctly. See the illustration. The lack of clearance is aggravated by two conditions. First, is the casting tolerances in the 2W6317 Elbow (1). Second, is the position of the tube nuts (4) flats and corners. A standard wrench is too thick to fit into the available space. When the jam nut (2) can not be tightened, a customer may be tempted to back the tee (3) out of the elbow until the jam nut can be tightened. This can cause the O-ring seal to try to seal against the tee's threads instead of the intended smooth undercut. The result can be an oil leak. Additional tightening of the jam nut will not stop the oil leak and may result in stripped threads in the elbow or on the tee.Solution:
If an oil leak is present where the tee (3) screws into the elbow (1), count the exposed threads on the tee that are between the jam nut (2) and the body of the tee. Normally, if the tee is correctly tightened, there should be .5 to 1.5 threads exposed. If there is more than 2 threads exposed, check to be sure the tee is correctly installed. To check for correct installation do the procedure that follows:1.Loosen the tube or tubes that are connected to the tee.2.Loosen the jam nut.3.Screw the tee all the way into the elbow.4.Unscrew the tee just far enough to align the tee with the tube or tubes to be connected to the tee.5.Install and tighten the nuts that connect the tube or tubes to the tee.6.Use a "thin" 1-1/2 inch wrench to tighten the jam nut. A "thin" wrench can be made by removing approximately 2.0 mm (.08 in) from each side of a "standard" wrench.The supplier of the 2W6317 Elbow is removing excess casting stock from the elbow. COPYRIGHT 1993 CATERPILLAR ALL RIGHT RESERVED